Development of Nonaggregating Poly-A Tailed Immunostimulatory A/D Type CpG Oligodeoxynucleotides Applicable for Clinical Use

Figure 1

Screening of human PBMC with several different polynucleotide tailed A/D type ODNs. Human PBMCs were stimulated with the indicated synthetic ODNs (1 μM) (Table 1) for 24 hours. IFN-α and IL-6 production in supernatants was measured by ELISA. (a) The requirement of CpG-motifs and G-hexamers for cytokine secretion from human PBMCs. Both IFN-α and IL-6 were secreted in a CpG motif dependent but G-hexamer sequence independent manner. (b) Comparison of tail backbones (phosphorothioate or phosphodiester). Cytokine secretion was dependent on phosphorothioate 40-mer tails (1, 3, and 5). ODNs with phosphodiester 40-mer tails showed almost no biological activity (2, 4, 6). The bar graphs indicate the concentrations from a single well of each stimulation. The results are representative of three different experiments consisting of two different donors (Exp-1 and Exp-2, Exp-3 and Exp-4).

(a)

(b)